Frost Line Depth in Santa Clara County, California

  • 5 verified codes nearby
  • Checked Oct 2026

No official local value

No official frost line depth is published for Santa Clara County.

Nearby official codes require 5–12 in (5 verified codes).

Source and how we checked

We searched this place’s own code and website and found no published frost line depth.

Climate: 45 nights a year at or below 32 °F (NOAA 1991–2020, Mt Hamilton, 8.8 mi).

Checked Oct 2026. Report a correction

Does Santa Clara County have an official frost line depth?

No adopted frost line depth found for Santa Clara County in its official documents (checked Oct 2026). The nearest official values, from codes we verified, are 5 to 12 in. Use the deepest of them until the building department confirms Santa Clara County’s own number.

What frost line depth does Santa Clara County use for footings under Table R301.2(1)? Is it 12 in, like Campbell?

How deep do footings, decks and water lines need to be in Santa Clara County?

Drawn with the deepest nearby official value (12 in). Confirm Santa Clara County’s own depth before you dig.

Project
House or garage footing in Santa Clara County: dig at least 12 in. grade 0 in 122436486072 12 in code minimum nearby codes 12 in, confirm locally dig 12 in

House or garage footing in Santa Clara County: dig at least 12 in (30 cm). Below the frost line and at least 12 in deep (IRC R403.1.4).

Using the nearby official value of 12 in until Santa Clara County confirms its own
ProjectDepthRule
House or garage footing12 inBelow the frost line and at least 12 in deep (IRC R403.1.4)
Deck footing (attached)12 inBelow the frost line and at least 12 in deep (IRC R507.3)
Water service line18 in6 in below the frost line and at least 12 in deep (IRC P2603.5)
Fence post bottom12 inNo code rule; common practice is below the frost line

Work out posts, concrete and footing sizes with the fence post depth calculator or the deck footing calculator.

How cold does it get in Santa Clara County?

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0°32°100° J F M A M J J A S O N D 32 °F

Santa Clara County never averages a low below freezing. 45 nights a year reach 32 °F or colder; Feb is coldest, with an average low of 37.8 °F.

NOAA 1991–2020 climate normals, Mt Hamilton station, 8.8 mi away, elevation 4,206 ft.

Monthly temperatures as a table
°FJanFebMarAprMayJunJulAugSepOctNovDec
Low39.137.838.940.747.455.965.164.660.352.443.438
High49.648.751.255.262.371.178.778.574.565.554.748.6
097 nightsSanta Clara County 45

Santa Clara County has more freezing nights than 198 of the 208 other California places we track. The California median is 3. Coldest: El Dorado County; mildest: San Diego.

What frost line depth do towns near Santa Clara County use?

5 official codes near Santa Clara County are verified; each links to its document.

0″12″24″36″48″36 mi0 miCampbell: 12 in, 15 miWatsonville: 12 in, 21 miSanta Cruz: 12 in, 26 miPalo Alto: 5 in, 28 miDublin: 12 in, 36 mi
Official frost line depths near Santa Clara County
PlaceVerified frost lineDistance
Campbell 12 in 15 mi away
Watsonville 12 in 21 mi away
Santa Cruz 12 in 26 mi away
Palo Alto 5 in 28 mi away
Dublin 12 in 36 mi away

How likely is the soil in Santa Clara County to heave?

USDA rates the sampled soil around Santa Clara County as 100% none for frost action (main soils: Los Gatos, Terrace escarpments, Azule).

USDA NRCS soil survey, 9 sample points within 2 mi. Higher frost action means more risk of heave; see frost heave.

Santa Clara County at a glance

Frost line depth
No official local value
Population (2023 est.)
1,877,592
Mean annual temperature
55.1 °F
ZIP codes (63)
94022 · 94024 · 94028 · 94040 · 94041 · 94043 · 94085 · 94086 · 94087 · 94089 · 94301 · 94303 · 94304 · 94305 · 94306 · 94550 · 95002 · 95008 · 95013 · 95014 · 95020 · 95023 · 95030 · 95032 · 95033 · 95035 · 95037 · 95046 · 95050 · 95051 · 95053 · 95054 · 95070 · 95076 · 95110 · 95111 · 95112 · 95113 · 95116 · 95117 · 95118 · 95119 · 95120 · 95121 · 95122 · 95123 · 95124 · 95125 · 95126 · 95127 · 95128 · 95129 · 95130 · 95131 · 95132 · 95133 · 95134 · 95135 · 95136 · 95138 · 95139 · 95140 · 95148

Sources

  • Climate: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00045933.
  • Soil: USDA NRCS Soil Survey (SSURGO) frost action ratings.
  • Code rules: International Residential Code R403.1.4, R507.3, P2603.5.

Checked Oct 2026. How we verify · Report a correction